1. Institute for Advanced Study Chengdu University Chengdu 610106 P.R. China
2. Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education and School of Materials Science and Engineering Xiangtan University Xiangtan Hunan 411105 China
3. Department of Materials Science and Engineering Southern University of Science and Technology Shenzhen Guangdong 518055 China
4. Shenzhen Key Laboratory of Nanobiomechanics Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen Guangdong 518055 China
5. MOE Key Laboratory of Deep Earth Science and Engineering College of Architecture and Environment Sichuan University Chengdu 610065 China